Apparatus for compacting powders



June .18, 1935.. H. J. GLAXNER 2,005,542

7 APPARATUS FOR COMPACTING POWDERS I Filed July 8, 1952 III viii E mun/1,27;

INVENTOR Her/flaw Jami 'laxrzer ATTQ R N EY5 gas is retained in the powder Patented June 18, 1935.

" UNITED STATES PATENT OFFICE Application July 8, 1932, Serial No. 621,419

8 Claims.

The invention relates to apparatus for compacting powders, andmore particularly to an improved apparatus adapted for the treatment of extremely light and fiufiy powders.

Certain powders, such as lamp black, carbon 5 black and the like, when in loose state, are extremely fine, very light and flufiy and contain a great deal of occluded gas. ders are compressed while confined in a chamber,

and expands the powder back to or toward its loose, fluify condition when the pressure is released. Furthermore, the powder so compressed has a tendency to scatter in dust-like fashion due to the escape or blowing out of the gas compressed there- 5 with.

One object of the present invention is to provide an improved apparatus for compressing a powder in such a manner as to permit the escape of the contained or occluded gas durin the application of pressure, whereby when the pressure is released the powder will retain its compact form.

.As an important feature of the present invention, the apparatus provides for the continuoustreatment of the powder, and includes two endless imperforate conveyer belts having a pair of surface facing converging straight runsv between which the powder is compressed. The angle between these runs is very small to effect gradual compression of the powder, and the sides of the belts are open to permit the contained gas to escape.

As an added featurepthe two belts at the apex of the converging runs pass over a single pulley, the powder being carried over the pulley between the belts where it forms a very thin compact layer. As this layer emerges from between the portions of the belts encircling the pulley, it is removed from one of the belts as flakes and conveyed to an outlet. The powder compressed by. my improved apparatus will retain its compact shape after the pressure is released, and is not liable to scatter in dust-like fashion inasmuch as the greater part of the occluded gas or air has been ejected therefrom. The flakes formed by means of this apparatus may be further reduced and compressed into blocks by more powerful mechanical pressures. If desired, the powders may be subjected to a preliminary compression action before being treated in the apparatus of the present construction.

As a further feature of the present invention, the whole apparatus is enclosed in a dust-proof When such powcasing, thereby preventing the escape of powder into the atmosphere.

In the accompanying drawing, there is shown for purposes of illustration, one form which the present invention may assure, and in which Fig. 1 is a vertical section through a casing enclosing the press, and

Fig. 2 is a section taken on the line 2-2 of Fig. 1.

In the specific embodiment of the present in- 10 vention there is provided a casing I!) which is substantially closed to render it dustproof, and in which is enclosed my improved belt press. This press includes an imperforate conveyer belt I I passing over a pair of pulleys l2 and I3. A second or outer imperforate conveyer belt 14 is provided, and is so located with respect to the belt H as to form a pair of straight converging runs therewith between which the powder is adapted to be compressed. The belt I l encircles the belt I I and passes over a pulley I 5 20 and the pulley I2, so that both belts pass over the latter pulley.

The lower run of the belts ll and M are substantially straight, nearly horizontal and converge towards the pulley l2, as shown in Fig. 1, the angle between the two runs being very small. The pulley I5 is sufficiently large so that the upper runs of the belts diverge towards the right.

The shafts of the pulleys extend beyond the sides of the casing land are supported in suitable bearing blocks at the, sides of the casing. The apertures in the casing through which these shafts extend are suitably covered by these blocks to prevent the es- 35 cape of any substantial amount of powder therethrough. One or more of the shafts is driven by any suitable power means from the outside of the casing. Suitable means are provided for tightening the belts H and M. For instance, the shafts of the pulleys I 3 and I5 may pass through elongated apertures l6 in the sides of the casing l0, and are journalled in bearing blocks I! on the outside of said casing l0. These 45 bearing blocks ll are mounted for slidable movement in guide yokes l8 fixed to the sides of the casing. Extending across one end of each yoke I8 is a crosspiece 19 supporting a screw 20 having one end thereof rotatably connected to the bearing block 11, while the other end is shaped to receive a suitable turning tool.

The powder to be compressed is fed into the interior of the casing Ill and upon the lower run of the belt I4 by suitable means, as for 55 l2, l3 and I5 may verging runs, it

instance a conveyer 22 having the receiving end outside the casing, and the discharge end mounted over the center of said belt l4. By means of this arrangement, the powder is dropped upon the center of the lower run of the belt l4 and is conveyed thereby towards the apex of the lower runs of the two belts. If desired, a spreader may be provided between the bottom runs of the belts, and advantageously takes the form of a-bar 23 extending between the sides of the casing l0 and serving to level off the powder as it is carried by the belt l4.

As the powder travels to the left between the two converging runs of the belts, it is very gradually compressed, and the occluded gas or air is ejected therefrom and permitted to escape between the open sides of the belts. The linear speed of the belts should be very low so as to reduce the tendency of the powder to scatter over the sides of the belts during its compression. The belts are driven at the same linear speed or may be driven at different linear speeds, so as to subject the powder to a slight frictional, stroking action. 1

As the powder reaches the apex of the conpulley l2 between the two belts, where it is subjected to a further pressure action, and where it forms a thin compressed layer. powder may be subjected to a further pressure action by means of a freely rotatable roller 24 yieldably pressed against the belt M on the pulley l2. For that purpose, the roller 24 is mounted on a shaft 25 passing through elongated slots in the sides of the casing, and journalled in bearing blocks 21 which cover said slots. Each block is slidably mounted in a yoke 28 connected to the side of the casing, and is urged towards the pulley l2 by means of a spring 29 disposed between a crosspiece 30 and the bearing block 21. The pressure of the spring against the bearing block may be adjusted by means of a screw 3| passing through the crosspiece 30 and having a plate 32 engaging the end of the spring 29.

After the compressed powder has traveled around the pulley l2 between the two belts H and I4, it emerges at the top between the two upper runs of the belts. As the belt I4 leaves the circular pulley l2 it straightens out and causes any layer of powder which may have adhered to the under surface thereof to break ofi into flakes and fall upon the upper run of the belt H. The belts II and M are advantageously made of rubber, and their facing surfaces between which the powder is compressed are made smooth to prevent the compressed powder from adhering too strongly thereto.

Adjoining the pulley I3 is a discharge conveyer 33 which receives the flakes leaving the belt H and conveys them to a point outside the casing Ill. The flakes do not adhere to the Outer surface of the belt II as said belt passes the pulley l3, since said belt in changing its curvature from a straight run to a circular run loosens the layer of compressed powder which may have adhered thereto. Any powder that falls off the sides of the conveyer 33 drops upon the lower run of the belt l4, and is reconveyed towards the converging runs of the two belts.

Also, any powder that might adhere to the inside surface of the upper run of the belt l4 after passing to the right of the pulley l3 will fall upon the lower run of said belt and will be reconveyed towards the-converging runs.

travels partway around the If desired, the- The powder being primarily along the center portion of the belt l4 causes a slight stretching of the center portion in passing around the pulley l2. Thus theedges of the two belts may come together and retard escape of the powder. The lower run of the belt "is also caused to assume a slightly trough-like form and thus aid in preventing the powder from falling off.

The casing I0 is not much wider than the width of the belts and the lower run of the belt I is spaced a short distance above the bottom of the casing. The powder which may fall oif the sides of the lower run of the belt l4 piles up on the bottom of the casing and forms embankments alongside of the belt. These embankments serve to retain the powder on the belt.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:--

1. An apparatus for compressing light, dry,

fine, fluffy powder, including a pair of spaced,

pulleys, having parallel axes disposed in a substantially horizontal plane, an endless imperforate conveyer belt tightly passing around said pair of pulleys and presenting substantially horizontal upper and lower runs, a third pulley disposed between said runs, and having its axis parallel to the axes of said first mentioned pulleys, said third pulley being spaced from said runs and having a diameter less than the distance between said runs in the vertical plane of the axis of said third pulley, a second imperforate conveyer belt passing tightly around said third pulley and one of said pair of pulleys, encircled by said first mentioned belt, and presenting upper and lower runs, the pair of upper and the pair of lower runs converging to the periphery of said last mentioned pulley, and means for delivering the powder to be compressed onto the lower run of one of said pairs, said-third pulley being sufficiently close' to one of the runs of said first mentioned belt so that the angle between the latter run and the adjacent run of the second mentioned belt is very small, whereby gasabove said powder and gas occluded within said powder may escape at a sufficiently low velocity so as not to disturb the layer of powder as the latter is advanced to one of said pair of pulleys.

2. An apparatus for compressing light, dry, fine, fiuffy powder, including a pair of spaced pulleys having parallel axes disposed in a substantially horizontal plane, an endless imperforate conveyer belt tightly passing around said pair of pulleys, and presenting substantially horizontal upper and lower runs, a third pulley disposed between said runs, and having its axis parallel to the axes of said first mentioned pulleys, said third pulley being spaced from said runs, and having a diameter less than the distance between said runs in the vertical plane of the axis of said third pulley, a second imperforate conveyer belt passing tightly around said third pulley and one of said pair of pulleys, encircled by said first mentioned belt, and presenting upper and lower runs, the pair of upper and the pair of lower runs converging to the periphery of said last mentioned pulley, means for delivering the power to be compressed-onto the lower run of one of said pairs, said third pulley being sufliciently close to one of the runs of said first mentioned belt so that the angle between the latter run and the adjacent run of the second mentioned belt is very small,

whereby gas above said powder and gas occluded within said powder may escape at a suficiently low velocity so as not to disturb the layer of powder as the latter is advanced to one of said pair of pulleys, and a casing enclosing said belts and pulleys and substantially closed to prevent escape therefrom of powder floating in the air in said casing.

3. An apparatus for compressing powder, including a pulley having a horizontal axis, a pair of endless imperforate conveyer belts passing around said pulley in superposed relationship, means horizontally spaced from said pulley in a direction at right angles to the axis thereof for supporting the inner belt, and of approximately the height of said pulley, means horizontally spaced. from said pulley in the same direction, and extending above and below said first mentioned means, for supporting the outer belt, whereby the upper and lower runs of both belts are in superposed relationship, corresponding runs being spaced apart and converging to said pulley and the angle between one pair of corresponding runs being very small to effect gradual compression of the powder therebetween, and the slow escape of occluded gas from said powder, and means for delivering the powder between the two runs of said latter pair.

4.- An apparatus for compressing powder, including a pulley having a horizontal axis, a pair of endless imperforate conveyer belts passing around said pulley in superposed relationship, means horizontally spaced from said pulley in a direction at right angles to the axis thereof for supporting the inner belt, and of approximately the height of said pulley, means'horizontally spaced from said pulley in the same direction, and extending above and below said first mentioned means for supporting the outer belt, whereby the upper and lower runs of both belts are in superposed relationship, corresponding runs being spaced apart and converging to said pulley, and the angle between one pair of corresponding runs being very small to effect gradual compression of the powder therebetween and the escape of air at low velocity from above said powder, means for delivering the powder between the two runs of said latter pair, a casing enclosing said pulley, belts and supporting means, and means adjacent to said first mentioned means for removing the compacted powder from said casing.

5. An apparatus for compressing powder, in-- cluding a pulley having the axis thereof substantially horizontal, an endless imperforate conveyer belt passing over said pulley, and supported by said pulley, means spaced from said pulley for supporting the belt and for tightly extending the portions of the belt substantially horizontally between said belt and said means, a second imperforate conveyer belt encircling said first mentioned belt and passing over said pulley, and means horizontally spaced to a greater distance from said pulley for supporting said second belt and for tightly extending the runs of the latter belt adjacent to the runs of the first belt, the juxtaposed runs being approximately horizontal and converging at a small angle towards said pulley, whereby the air above said powder escapes at low velocity.

6. An apparatus for compressing light, fine, fiufiy powder, including a pair of endless imperforate conveyer belts, one of said belts being substantially longer than the other, a pulley around which said belts extend in direct superposed relationship, means spaced from said pulley for supporting said belts in encircling relationship and for tightly extending said belts in directions to form a pair of substantially horizontal superposed spaced runs converging at a small angle to said pulley and permit escape of air at low velocity as said powder approaches said pulley and adapted to receive powder therebetween and compress it as said belts travel toward and around said pulley, a casing enclosing said belts and substantially closed to prevent escape of any substantial amount of dust therefrom, and having an opening in one wall thereof, and a conveyer passing through said opening, and having the receiving end thereof outside the casing and the discharge end between the converging horizontal runs of said imperforate belts.

7. An apparatus forcompressing light, fine, fluffy, dry powder, including a pair of spaced pulleys having parallel axes disposed in a substantially horizontal plane, an endless imperforate conveyer belt passing around said pair of pulleys and presenting substantially horizontal upper and lower runs, a third pulley disposed between said runs and having its axis parallel to the axes of said first mentioned pulleys, said third pulley being spaced from said runs, and having a diameter less than the distance between said runs in the vertical plane of the axis of said third pulley, a second imperforate conveyer belt tightly passing around said third pulley and one of said pair of pulleys, encircled by said first mentioned pulley, and presenting upper and lower runs, the pair of upper and the pair of lower runs converging to the periphery of said last mentioned pulley, said third pulley being sufliciently close to one of the runs of said first mentioned belt so that the angle between the latter run and the corresponding run of the second mentioned belt is very small, and means for independently moving said third pulley and the other one of said pair 'of pulleys in a substantially horizontal direction, whereby the belts may be independently tightened without changing the angle between corresponding runs.

8. An apparatus for compressing light, fine,

dry, fiufiy powder, including a pulley having a horizontal axis, a pair of endless imperforate conveyer belts passing around said pulley in superposed relationship, means horizontally spaced from said pulley in a direction at right angles to the axis thereof for supporting the inner belt, means horizontally spaced from said pulley in the same direction, and extending above and below said first mentioned means, for supporting the outer belt, whereby the upper and lower .runs of bothbelts are in superposed relationship,

corresponding runs being spaced apart and converging to said pulley, means for delivering the powder to be compressed onto the lower of said converging runs, the angle between one pair of said corresponding runs being very small to effect the removal of gas from above and within said powder at low velocity and the gradual compression of said powder and means for tightening said belts independently of each other without changing the angle between corresponding runs of said belts.

HERMAN JACOB GLAXNER. 

